Re: [Starpu-devel] Constructing codelet-chain loop

[Albert Sidelnik <sidelnik@gmail.com>]

I should mention a few assumptions that I am making in this test case:

1) By setting regenerate = 1 for all tasks,  my assumption is that
when tasks are regenerated, they preserve their tag dependences.
2) If each task has only one predecessor that it is dependent on, I
can resolve that dependence directly through a starpu_tag_notify()
call in order for that task to execute
3) The task graph is constructed a priori (I never need to resubmit the task)

For the previous test case, if I were not to utilize tags (and
starpu_tag_notify), and only rely on resubmitting tasks similar to the
test case in main/subgraph_repeat_regenerate.c, things work It's only
when dealing with the tags, that things fail.

On Wed, Apr 18, 2012 at 1:10 PM, Albert Sidelnik <sidelnik@gmail.com> wrote:
> I'm trying emulate a "do-while" loop strictly using codelets, but my
> program seems to be hanging, and I don't know if its user error, or if
> there is a bug in the runtime (more than likely it's user error :-)).
> The test is fairly simple, it creates a codelet for each component of
> the do-while loop (loop start, body of loop, branch). In the "branch"
> codelet, based on a given condition, it will perform a
> starpu_tag_notify() to perform the backedge or to exit the loop. What
> happens is that the loop will perform a couple iterations, and then
> just hang. I've attached the simple test to demonstrate this.
>
> thanks!
> --Albert